Although George W. Bush is a man without intellectual pretensions, his departure from office brings down the curtain on a distinctive era of American political thought. Ideas that recently qualified as smart have suddenly become passé. Propositions once alluringly au courant now appear not simply obsolete but absurd. The bubble of American triumphalism has burst.

That bubble first appeared as the cold war was ending. Triumphalist thinking derived from two widely held perceptions. The first was that the unraveling of the Soviet empire had brought history to a definitive turning point. According to this view, the annus mirabilis of 1989 truly was a year of wonders, sweeping aside the old order and opening the door to vast new possibilities. The second conviction was that it was up to the United States to determine what was to come next. Basic arithmetic told the story: there had previously been two superpowers; now only one remained. Henceforth, the decisions that mattered would be Washington’s to make.

Proponents of triumphalism vied with one another in explaining the implications of these two notions. First out of the gate was the scholar Francis Fukuyama. Even before the Berlin Wall had fallen, Fukuyama rendered his verdict on the entire twentieth century: Democratic capitalism had won. For Fukuyama, this “triumph of the West” found expression “in the total exhaustion of viable systematic alternatives to Western liberalism,” embodied above all by the United States. Viewed from this perspective, the passing of the cold war signified “the end point of mankind’s ideological evolution and the universalization of Western liberal democracy as the final form of human government.”

Fukuyama titled the essay that made him famous “The End of History?”—the question mark suggesting a lingering circumspection. Soon thereafter circumspection fell from favor. Certainty emerged as a triumphalist hallmark.

Thus in 1990, the columnist Charles Krauthammer, less impressed with ideology than with power, weighed in with his own interpretation of what the collapse of the Soviet empire had wrought. History, he wrote, had now arrived at a “unipolar moment.” Krauthammer did not mince words: in the post–cold war order, only one country really mattered. “The center of world power is the unchallenged superpower,” he wrote. The key to sustaining this favorable situation was for the United States to make the most of it, “unashamedly laying down the rules of world order” and then employing its preeminent military to enforce those rules.

In 1996, William Kristol and Robert Kagan chimed in, staking out a position that blended Fukuyama with Krauthammer. For these two neoconservatives, fulfilling history’s purpose and perpetuating American primacy formed two sides of the same coin. The relationship between the two was reciprocal: American assertiveness would hasten history’s arrival at its predetermined destination where American values would prevail everywhere. Kristol and Kagan dismissed as poppycock “misguided warnings of imperial overstretch.” The United States had a clear “responsibility to lead the world.” To make good on that responsibility, they advocated a strategy of “benevolent global hegemony” informed by “military supremacy and moral confidence.”

Next came New York Times columnist Thomas Friedman, touting the transformative impact of globalization, which on closer examination turned out to be a euphemism for Americanization. The ultimate goal, Friedman wrote in 1999, was “the spread of free-market capitalism to virtually every country in the world”—a process that would put “a Web site in every pot, a Pepsi on every lip, [and] Microsoft Windows in every computer.” Yet none of this was going to occur without the backing of hard power. “The hidden hand of the market will never work without a hidden fist,” Friedman declared. “And the hidden fist that keeps the world safe for Silicon Valley’s technologies is called the United States Army, Air Force, Navy, and Marine Corps.”

Friedman’s essay appeared as a cover story in the New York Times Magazine. Accompanying the cover illustration—a clenched fist, vividly painted with the Stars and Stripes—was this text: “For globalism to work, America can’t be afraid to act like the almighty superpower that it is.”

Then came 9/11. Paradoxically, this catastrophe served not to undermine but to affirm this conception of the United States as almighty superpower. Triumphalism now became official dogma, its principal tenets deployed to explain and justify the Bush administration’s global war on terror.

Channeling Fukuyama, for example, President Bush announced in 2002 that there existed but “a single sustainable model for national success—freedom, democracy, and free enterprise.” Plausible alternatives simply did not exist: this was history’s irreversible judgment. Trumpeting the “unparalleled strength” of America’s armed forces, the president vowed to enhance that strength even further, thereby dissuading anyone from entertaining ambitions of “surpassing, or even equaling, the power of the United States.” Thus did Bush endorse the concept of unipolarity without actually using the word. The president likewise refrained from any explicit reference to hegemony. Yet in promulgating a doctrine of preventive war and in refusing to be encumbered by international norms not to its liking, his administration asserted hegemonic prerogatives. Along with all of this muscle-flexing came a Friedmanesque promise to “ignite a new era of global economic growth through free markets and free trade.”

In short, after 9/11 President Bush put the triumphalist hypothesis to the test. As he left office, the results of that test clearly presented themselves. What we’ve learned is this: First, liberalism’s widely touted victory is at best incomplete. Especially in the Islamic world, a stubborn search for alternatives persists. Our insistence that others do things our way exacerbates the opposition we face. Second, unipolarity is a chimera, a dangerous refusal to acknowledge the world’s complexity. Third, to pursue global hegemony is to court bankruptcy. To persist in imagining otherwise will only hasten America’s decline. Fourth, although globalization may be real, the United States can neither direct its course nor fully insulate itself from its adverse effects. Ideas have consequences.

Post–cold war triumphalism produced consequences that are nothing less than disastrous. Historians will remember the past two decades not as a unipolar moment, but as an interval in which America succumbed to excessive self-regard. That moment is now ending with our economy in shambles and our country facing the prospect of permanent war.

Don’t expect triumphalists to recant or apologize. Yet their time has passed. The Age of Triumphalism has ended. The Age of Muddling Through has commenced. In this new era, over which Barack Obama will preside, grandiose ideas will take a back seat to figuring out what actually works and calculating how much we can afford. Instead of looking to transform the world, the imperative of this new age is to preserve what’s left and restore what’s been lost. The nattering about the United States as an almighty superpower has ceased. For this at least we should be grateful.